The aim of this research is to accurately predict three-dimensional displacements of teeth for any applied force system, to quantify these results in terms of centers of rotation, and to estimate stress-strain characteristics at the tooth-periodontal ligament and periodontal ligament-alveolar bone interfaces. The translations and rotations of teeth will be determined using non-invasive, state-of-the-art techniques of hologram interferometry. The experimental data will also be used to develop a mathematical model for prediction of stress-strain characteristics of the periodontal ligament; this model will by synthesized using the finite element technique. The synthesis technique which will be developed herein will be a considerable improvement over present analytical techniques. Stresses in the primate periodontal ligament will be estimated and related to one remodeling studied histologically. Primary displacements (before any biologic changes such as bone apposition and bone resportion take place) of skull bones will be studied and related to secondary displacements (when biologic changes are present) using hologram interferometry.